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Comparison · 2 models · Updated Oct 4, 2026

Grok 4.3 vs GPT-5.4 nano

Too close to call on our weighted score (GPT-5.4 nano 68, Grok 4.3 67). The right pick depends on what you value most.

  1. xAI

    Grok 4.3

    Released Apr 17, 2026

    67/100
    • ECI149.2
    • Price$1.25 / $2.50
    • Context1M
    Full specs Remove Grok 4.3

  2. OpenAI

    GPT-5.4 nano

    Released Mar 17, 2026

    68/100
    • ECI145.8
    • Price$0.20 / $1.25
    • Context400K
    Full specs Remove GPT-5.4 nano

  3. Add a model

    Make it a three-way comparison.

01 — Verdict

Too close to call

It is close. Our weighted score puts them within 1 points (GPT-5.4 nano 68/100, Grok 4.3 67/100), so choose by what matters most for your work: Grok 4.3 for raw capability and GPT-5.4 nano on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityGrok 4.3Capabilities Index (ECI): Grok 4.3 149.2 · GPT-5.4 nano 145.8
  • Lowest priceGPT-5.4 nanoGPT-5.4 nano $0.463 · Grok 4.3 $1.56 per 1M tokens (3:1 blend)
  • Longest contextGrok 4.3Grok 4.3 1,000,000 · GPT-5.4 nano 400,000 tokens
  • Widest inputsGrok 4.3Grok 4.3: Text, Images, PDFs · GPT-5.4 nano: Text, Images
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGrok 4.3GPT-5.4 nano
CapabilityCapabilities Index (ECI)50%7773
Price25%4166
Inputs & features15%8070
Context window10%6044
Overall100%67/10068/100
02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

Grok 4.3 vs GPT-5.4 nano specifications side by side
SpecificationGrok 4.3xAIGPT-5.4 nanoOpenAI
Capability
Capabilities Index (ECI)149.2 (best)145.8
ECI rank#55 of 148 (best)#75 of 148
GPQA DiamondGraduate-level science questions88.8% (best)78.5%
FrontierMath Tiers 1–3Research-level mathematics42.8%44.9% (best)
OTIS Mock AIME 2024–2025Competition mathematics93.3% (best)87.8%
SimpleQA VerifiedShort factual questions33.2% (best)11.7%
Price per million tokens
Input$1.25$0.20 (best)
Output$2.50$1.25 (best)
Cached input$0.20$0.02 (best)
Blended (3:1)$1.56$0.463 (best)
Long-context rateOver 200K: $2.50 / $5.00Same rate
Price sourceOfficial xAI APIOfficial OpenAI API
Limits
Context window1,000,000 tokens (best)400,000 tokens
Max output30,000 tokens128,000 tokens (best)
Inputs and features
TextYesYes
ImagesYesYes
PDFsYesNo
AudioNoNo
VideoNoNo
ReasoningYeslow · medium · highYeslow · medium · high · xhigh
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDgrok-4.3gpt-5.4-nano
API providers27 (best)26
ReleasedApr 17, 2026Mar 17, 2026
Knowledge cutoff—Aug 31, 2025
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • Grok 4.3$17.50
  • GPT-5.4 nano$4.50
04 — Questions

Which should you choose?

Which is better: Grok 4.3 or GPT-5.4 nano?

It is close. Our weighted score puts them within 1 points (GPT-5.4 nano 68/100, Grok 4.3 67/100), so choose by what matters most for your work: Grok 4.3 for raw capability and GPT-5.4 nano on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Grok 4.3 or GPT-5.4 nano?

GPT-5.4 nano is cheaper at $0.20 input / $1.25 output per million tokens (official OpenAI API price). Grok 4.3 costs $1.25 input / $2.50 output per million tokens (official xAI API price). At a typical mix of three input tokens to one output token, that is $0.463 per million tokens for GPT-5.4 nano versus $1.56 for Grok 4.3 (3.4× as much).

Which scores higher on benchmarks?

Grok 4.3 scores higher on the Capabilities Index (ECI): Grok 4.3 149.2 (#55 of 148) and GPT-5.4 nano 145.8 (#75 of 148). The confidence ranges of the top two overlap (147.6–150.8 vs 143.2–147.7), so treat the gap as small. On individual benchmarks: GPQA Diamond — Grok 4.3 88.8%, GPT-5.4 nano 78.5%; FrontierMath Tiers 1–3 — GPT-5.4 nano 44.9%, Grok 4.3 42.8%; OTIS Mock AIME 2024–2025 — Grok 4.3 93.3%, GPT-5.4 nano 87.8%; SimpleQA Verified — Grok 4.3 33.2%, GPT-5.4 nano 11.7%.

Which is better for coding?

There are no published SWE-bench Verified results for Grok 4.3 and GPT-5.4 nano yet, so there is no like-for-like coding score. On overall capability, Grok 4.3 leads, which tends to carry over to coding, but test on your own codebase. Both support tool calling for agent workflows.

Which has the bigger context window?

Grok 4.3 has the largest context window at 1,000,000 tokens, against 400,000 for GPT-5.4 nano. Maximum output per response: Grok 4.3 up to 30,000, GPT-5.4 nano up to 128,000 tokens.

Which can read images, PDFs, audio or video?

Grok 4.3 accepts text, images and PDFs; GPT-5.4 nano accepts text and images. Grok 4.3 handles the widest range of inputs.

Are any of these open source?

No. Grok 4.3 and GPT-5.4 nano are proprietary and only available through APIs and apps.

Which is newer?

Grok 4.3 is the newest, released Apr 17, 2026. GPT-5.4 nano came out Mar 17, 2026. Knowledge cutoff: GPT-5.4 nano Aug 31, 2025.

How do you decide the winner?

Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.

05 — Keep comparing

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